Abstract
BACKGROUND: This study proposed a novel maxillary transverse deficiency diagnostic method and evaluated the skeletal Class I and the mild skeletal Class III groups. METHODS: Pre-treatment data from 30 mild skeletal Class III and 30 skeletal Class I patients were collected and uploaded to the Emeiqi Case Management System to design the ideal teeth positions. On these positions, the first bi-molars width was measured at the central fossa and center resistance, the maxillary first bi-premolars width was measured at the central fossa, and the mandibular first bi-premolars width was measured at the distal contact point by Mimics, then width differences of two groups were calculated respectively. RESULTS: At ideal teeth positions, there was no statistically significant difference in the maxillomandibular width in the premolar area between the two groups, but there was in the molar area, and this difference was caused by the difference in mandible width between the two groups. CONCLUSIONS: We proposed a new transverse diagnostic method and found that even the Class I group was not quite up to standard in the molar area on ideal teeth positions, and the Class III group had more severe maxillary transverse deficiency than the Class I group. Meanwhile, the maxillary transverse deficiency in the Class III group was mainly caused by the larger width of the mandible.